Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "<link rel=\"canonical\" href=\"(.*?)\">"; final String string = "const regex = /\"sku\": \"(.*?)\"/gm;\n\n" + "// Alternative syntax using RegExp constructor\n" + "// const regex = new RegExp('\"sku\": \"(.*?)\"', 'gm')\n\n" + "const str = ``<!DOCTYPE html>\n" + "<!-- saved from url=(0044)https://www.daz3d.com/karmen-9-hd-pro-bundle -->\n" + "<html xmlns=\"http://www.w3.org/1999/xhtml\" xml:lang=\"en\" lang=\"en\" class=\"\"><head><meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\">\n\n" + "<title>Karmen 9 HD Pro Bundle | Daz 3D</title>\n" + "<meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">\n" + "<meta name=\"description\" content=\"&lt;p&gt;Introducing the Karmen 9 HD Pro Bundle. This all-inclusive bundle features a vibrant makeup look, expressions, a curly and braided bun hairstyle, apocalyptic-inspired outfits, Elemental Mage and Shadow Realm attire, and even monstrous poses to immerse \">\n" + "<meta name=\"keywords\" content=\"Karmen 9 HD Pro Bundle\">\n" + "<meta http-equiv=\"X-UA-Compatible\" content=\"IE=edge\">\n" + "<meta name=\"robots\" content=\"INDEX,FOLLOW,noai, noimageai\">\n" + "<link rel=\"icon\" href=\"https://www.daz3d.com/static/images/favicon.ico\" type=\"image/x-icon\">\n" + "<link rel=\"shortcut icon\" href=\"https://www.daz3d.com/static/images/favicon.ico\" type=\"image/x-icon\">\n" + "<!--[if lt IE 7]>\n" + "<script type=\"text/javascript\">\n" + "//<![CDATA[\n" + " var BLANK_URL = '/js/blank.html';\n" + " var BLANK_IMG = '/js/spacer.gif';\n" + "//]]>\n" + "</script>\n" + "<![endif]-->\n" + "<link rel=\"stylesheet\" href=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/design-533ce80c63b6085aedc802b14d1faa79.css\" about=\"0\">\n" + "<link rel=\"stylesheet\" href=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/product_zoom-5de5dd875434871413473d85f684dcfc.css\" about=\"1\">\n" + "<style>\n" + " @keyframes spinner {\n" + " 0% {\n" + " transform: translateY(-50%) rotate(0deg);\n" + " }\n\n" + " 100% {\n" + " transform: translateY(-50%) rotate(360deg);\n" + " }\n" + " }\n\n" + " .spinner::after {\n" + " animation: 1.5s linear infinite spinner;\n" + " animation-play-state: inherit;\n" + " border: solid 3px #cfd0d1;\n" + " border-bottom-color: #1c87c9;\n" + " border-radius: 50%;\n" + " content: \"\";\n" + " height: 20px;\n" + " width: 20px;\n" + " display: inline-flex;\n" + " flex-direction: column;\n" + " padding-bottom: 5px;\n" + " }\n" + " </style>\n" + "<script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/getIds\" type=\"text/javascript\" async=\"\"></script><script type=\"text/javascript\" id=\"www-widgetapi-script\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/www-widgetapi.js.download\" async=\"\"></script><script async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/fbevents.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/bat.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/pixel.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/analytics.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/js\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/destination\"></script><script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/tag.js.download\" type=\"text/javascript\" async=\"\" id=\"cjapitag\"></script><script async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/affirm.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/0\"></script><script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/core-ed1ca31447e4f2e9bbf6d9ef38afe3c6.js.download\"></script>\n" + "<style>\n" + " @keyframes spinner {\n" + " 0% {\n" + " transform: translateY(-50%) rotate(0deg);\n" + " }\n\n" + " 100% {\n" + " transform: translateY(-50%) rotate(360deg);\n" + " }\n" + " }\n\n" + " .spinner::after {\n" + " animation: 1.5s linear infinite spinner;\n" + " animation-play-state: inherit;\n" + " border: solid 3px #cfd0d1;\n" + " border-bottom-color: #1c87c9;\n" + " border-radius: 50%;\n" + " content: \"\";\n" + " height: 20px;\n" + " width: 20px;\n" + " display: inline-flex;\n" + " flex-direction: column;\n" + " padding-bottom: 5px;\n" + " }\n" + " </style>\n" + "<script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/zoom-fee76dde1f2c855960b29036b231c115.js.download\"></script>\n" + "<script type=\"application/ld+json\">{\n" + " \"brand\": {\n" + " \"name\": \"Daz 3D\",\n" + " \"@type\": \"Brand\"\n" + " },\n" + " \"@context\": \"https://schema.org/\",\n" + " \"description\": \"Introducing the Karmen 9 HD Pro Bundle. This all-inclusive bundle features a vibrant makeup look, expressions, a curly and braided bun hairstyle, apocalyptic-inspired outfits, Elemental Mage and Shadow Realm attire, and even monstrous poses to immerse your character into any narrative from modern desert to fantasy to horror.\",\n" + " \"image\": \"https://gcdn.daz3d.com/p/91909/i/shimuzu_Karmen_Pro_Bundle.jpg\",\n" + " \"name\": \"Karmen 9 HD Pro Bundle\",\n" + " \"offers\": {\n" + " \"availability\": \"https://schema.org/InStock\",\n" + " \"itemCondition\": \"https://schema.org/NewCondition\",\n" + " \"price\": 185.99,\n" + " \"priceCurrency\": \"USD\",\n" + " \"@type\": \"Offer\"\n" + " },\n" + " \"sku\": \"91909\",\n" + " \"@type\": \"Product\"\n" + "}</script>\n" + "<link rel=\"canonical\" href=\"https://www.daz3d.com/karmen-9-hd-pro-bundle\">\n" + "<script>\n" + " if (!daz) { var daz = {}; };\n" + " daz.api = new DazApi()\n\n" + " from 331.2deg,\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1)\n" + " )\n" + " 1;\n" + " }\n" + " 93% {\n" + " border-image: conic-gradient(\n" + " from 334.8deg,\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1)\n" + " )\n" + " 1;\n" + " }\n" + " 94% {\n" + " border-image: conic-gradient(\n" + " from 338.4deg,\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1)\n" + " )\n" + " 1;\n" + " }\n" + " 95% {\n" + " border-image: conic-gradient(\n" + " from 342deg,\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1)\n" + " )\n" + " 1;\n" + " }\n" + " 96% {\n" + " border-image: conic-gradient(\n" + " from 345.6deg,\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1)\n" + " )\n" + " 1;\n" + " }\n" + " 97% {\n" + " border-image: conic-gradient(\n" + " from 349.2deg,\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1)\n" + " )\n" + " 1;\n" + " }\n" + " 98% {\n" + " border-image: conic-gradient(\n" + " from 352.8deg,\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1)\n" + " )\n" + " 1;\n" + " }\n" + " 99% {\n" + " border-image: conic-gradient(\n" + " from 356.4deg,\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1)\n" + " )\n" + " 1;\n" + " }\n" + " 100% {\n" + " border-image: conic-gradient(\n" + " from 360deg,\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1),\n" + " var(--border-color-2),\n" + " var(--border-color-1)\n" + " )\n" + " 1;\n" + " }\n" + " }\n" + " }\n\n" + " /* END rotate bonus box border */\n" + " /* BEGIN falling stars animation */\n\n" + " .bg-stars {\n" + " width: 100%;\n" + " height: 100%;\n" + " position: absolute;\n" + " top: 0;\n" + " left: 0;\n" + " overflow: hidden;\n" + " }\n\n" + " .bg-stars .bg-star {\n" + " font-size: 1em;\n" + " position: absolute;\n" + " top: -25px;\n" + " color: yellow;\n" + " user-select: none;\n" + " cursor: default;\n" + " text-shadow: 0 0 1px #000;\n" + " animation-name: fallingStars;\n" + " animation-duration: 5s;\n" + " animation-timing-function: linear;\n" + " animation-iteration-count: infinite;\n" + " animation-play-state: running;\n" + " z-index: -1;\n" + " }\n" + " \n" + " .bg-stars .bg-star:nth-of-type(1) {\n" + " left: 10%;\n" + " -webkit-animation-delay: 1s, 1s;\n" + " animation-delay: 1s, 1s;\n" + " }\n\n" + " .bg-stars .bg-star:nth-of-type(2) {\n" + " left: 20%;\n\n\n" + "</div></body></html>(`;\n" + "let m;\n\n" + "while ((m = regex.exec(str)) !== null) {\n" + " // This is necessary to avoid infinite loops with zero-width matches\n" + " if (m.index === regex.lastIndex) {\n" + " regex.lastIndex++;\n" + " }\n" + " // The result can be accessed through the `m`-variable.\n" + " m.forEach((match, groupIndex) => {\n" + " console.log(`Found match, group ${groupIndex}: ${match}`);\n" + " });\n" + "}\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html